Due to the widespread use of carbon fiber reinforced polymer/plastic(CFRP),the nondestructive structural health monitoring for CFRP is playing an increasingly essential role.As a nonrad iative,noninvasive and nondestr...Due to the widespread use of carbon fiber reinforced polymer/plastic(CFRP),the nondestructive structural health monitoring for CFRP is playing an increasingly essential role.As a nonrad iative,noninvasive and nondestructive detection technique,planar electrical capacitance tomography(PECT)electrodes array is employed in this paper to reconstruct the damage image according to the calculated dielectric constant changes.The shape and duty ratio of PECT electro-des are optimized according to the relations between sensitivity distribution and the dielectric constant of different anisotropic degrees.The sensitivity matrix of optimized PECT sensor is more uniform as the result shows,because the sensitiv-ity of insensitivity area can be increased by adding rotation of optimized electro-des.The reconstructed image qualities due to different PECT arrays and different damage locations are investigated at last.The simulation results indicate that:PECT can be used to detect the surface damage of CFRP;the sensitivity matrix of PECT for CFRP is highly relevant with the degree of anisotropic dielectric con-stant;the rotatable PECT sensor with rotation has better performance in unifor-mity of sensitivity;for different damage locations,the rotatable sensor with rotation has better image quality in most cases.展开更多
Background Although Multi-planar reconstruction （MPR） has been considered a diagnostic imaging technique that observes more perspectives for diseases,few people have applied it surgically.In fact,MPR is also very us...Background Although Multi-planar reconstruction （MPR） has been considered a diagnostic imaging technique that observes more perspectives for diseases,few people have applied it surgically.In fact,MPR is also very useful to clinical operation,especially for patients with type B aortic dissection.It helps the surgeon to locate accurately with more information about aortic dissection,so that the safety and effectiveness of operation can be improved.This study examined the application of the MPR in intraoperative DSA imaging for precise positioning by accurately obtaining a crosssection,a spin angle of the coronal plane,and a tilt angle of the sagittal plane in treatment of type B aortic dissection.Methods The conventional and the MPR approaches were compared on positioning the aortic arch for surgery.A group of 40 patients （group A） and another group of 42 patients （group B） was sampled.About the comparison of baseline characteristics,a fourfold table X2 test was conducted on gender,and two independent samples t-test was applied to age between group A and group B.Spin as well as tilt angles for group A were obtained from the patients using both approaches,and their effectiveness was compared with pair t-tests; The MPR data guided stent-grafting in this group.Stent graft placement of group B was based on the conventional approach.Percentages of proximal distributed markers as well as incidences of complications were collected from both groups after stent graft placement.They were also compared with a fourfold table X2 test.Results Gender difference was not found between group A and group B （X2=0.80,P ＞0.05）,and age difference was not statistically significant （F=2.55,homogeneity of variance,t=-1.46,P ＞0.05）.A significant difference was found between the conventional and the MPR approaches for spin angle （t=9.17） as well as tilt angle （t=-2.07）,P ＜0.05.Percentage of proximal distributed markers （5.0％） of group A was significantly lower than that of group B （42.9％）,X2=15.92,P ＜0.05;and incidence of complications （5.0％） of group A was also significant lower than that of group B （21.4％）,X2=4.76,P ＜0.05.Conclusions Application of the MPR facilitated intraoperative angle adaption and led to satisfactory DSA.It is feasible in endovascular treatment of type B aortic dissection,and can effectively and safely guide surgical operations.展开更多
The object of this series of papers is to show that every planar graph ofminimum degree at least 3 is edge reconstructible. In this paper, we prove that such agraph with connectivity 2 is edge reconstructible.
基金This work is supported by the National Natural Science Foundation of China(Grant No.61871379).
文摘Due to the widespread use of carbon fiber reinforced polymer/plastic(CFRP),the nondestructive structural health monitoring for CFRP is playing an increasingly essential role.As a nonrad iative,noninvasive and nondestructive detection technique,planar electrical capacitance tomography(PECT)electrodes array is employed in this paper to reconstruct the damage image according to the calculated dielectric constant changes.The shape and duty ratio of PECT electro-des are optimized according to the relations between sensitivity distribution and the dielectric constant of different anisotropic degrees.The sensitivity matrix of optimized PECT sensor is more uniform as the result shows,because the sensitiv-ity of insensitivity area can be increased by adding rotation of optimized electro-des.The reconstructed image qualities due to different PECT arrays and different damage locations are investigated at last.The simulation results indicate that:PECT can be used to detect the surface damage of CFRP;the sensitivity matrix of PECT for CFRP is highly relevant with the degree of anisotropic dielectric con-stant;the rotatable PECT sensor with rotation has better performance in unifor-mity of sensitivity;for different damage locations,the rotatable sensor with rotation has better image quality in most cases.
文摘Background Although Multi-planar reconstruction （MPR） has been considered a diagnostic imaging technique that observes more perspectives for diseases,few people have applied it surgically.In fact,MPR is also very useful to clinical operation,especially for patients with type B aortic dissection.It helps the surgeon to locate accurately with more information about aortic dissection,so that the safety and effectiveness of operation can be improved.This study examined the application of the MPR in intraoperative DSA imaging for precise positioning by accurately obtaining a crosssection,a spin angle of the coronal plane,and a tilt angle of the sagittal plane in treatment of type B aortic dissection.Methods The conventional and the MPR approaches were compared on positioning the aortic arch for surgery.A group of 40 patients （group A） and another group of 42 patients （group B） was sampled.About the comparison of baseline characteristics,a fourfold table X2 test was conducted on gender,and two independent samples t-test was applied to age between group A and group B.Spin as well as tilt angles for group A were obtained from the patients using both approaches,and their effectiveness was compared with pair t-tests; The MPR data guided stent-grafting in this group.Stent graft placement of group B was based on the conventional approach.Percentages of proximal distributed markers as well as incidences of complications were collected from both groups after stent graft placement.They were also compared with a fourfold table X2 test.Results Gender difference was not found between group A and group B （X2=0.80,P ＞0.05）,and age difference was not statistically significant （F=2.55,homogeneity of variance,t=-1.46,P ＞0.05）.A significant difference was found between the conventional and the MPR approaches for spin angle （t=9.17） as well as tilt angle （t=-2.07）,P ＜0.05.Percentage of proximal distributed markers （5.0％） of group A was significantly lower than that of group B （42.9％）,X2=15.92,P ＜0.05;and incidence of complications （5.0％） of group A was also significant lower than that of group B （21.4％）,X2=4.76,P ＜0.05.Conclusions Application of the MPR facilitated intraoperative angle adaption and led to satisfactory DSA.It is feasible in endovascular treatment of type B aortic dissection,and can effectively and safely guide surgical operations.
基金This research is supported by the National Natural Science Foundation of China.
文摘The object of this series of papers is to show that every planar graph ofminimum degree at least 3 is edge reconstructible. In this paper, we prove that such agraph with connectivity 2 is edge reconstructible.
